INSERT, UPDATE and DELETE

Change the data: add rows, change values in rows, and remove rows.

Syntax

INSERT INTO table_name (columns) VALUES (values);
UPDATE table_name SET column = value WHERE condition;
DELETE FROM table_name WHERE condition;

UPDATE products SET unit_price = unit_price + 0.10 WHERE category = 'drinks';

Raises the price of each drink by 0.10; other products are untouched.

Tables used: products. Try it in a lesson below.

UPDATE and DELETE without WHERE change or remove every row. Run a SELECT with the same WHERE first to check the rows.
Changes apply straight away in a real database. Practise in a copy, or inside a transaction you can roll back.